Defense attorneys sometimes warn that bad legal precedents are created through criminal cases against organized crime, because prosecutors take advantage of the fact that most people are willing to overlook legal niceties when hardened criminals are charged.

A similar dynamic appears to involve statistics and sex trafficking. Because sex trafficking is considered horrific, politicians appear willing to cite the flimsiest and most poorly researched statistics — and the media is content to treat the claims as solid facts. After Klobuchar made these remarks, publications across Minnesota, including the Minneapolis Star-Tribune, repeated them without any due diligence.

Many politicians have touted this statistic, but Klobuchar appears particularly fond of it. She even cited it in an opinion article, co-written with Cindy McCain, that appeared in The Washington Post in 2014.

But, if you think about it for half a minute, this statistic makes little sense on its face. After all, if it is the “average,” then for all those who entered trafficking at age 16 or 17, there have to be nearly equivalent numbers who entered at age 9 or 10. But no one seriously believes that. Upon investigation, this claim crumbles to dust.

The Facts

Klobuchar’s staff claimed they got the statistic from U.S. government agencies such as the FBI. Indeed, when the stat was mentioned in her Washington Post article, a link was provided to the Web site of the FBI, though not to any particular study.

But FBI spokesmen say this is not their figure. The Justice Department also says it is not a DOJ figure.

The FBI did once post on the Web an opinion article, written by Baltimore prosecutors, that mentioned the claim that the average age was 13. That article cited as a source a 2001 report written by Richard J. Estes and Neil Weiner of the University of Pennsylvania. But that’s not the same as an “FBI number.”

The data in the report, which was not peer-reviewed, is almost two decades old. The primary author no longer supports it, saying it is outdated. “The world of the 1990s … was quite a different one from that in which we live today,” Estes told The Fact Checker.

In any case, there is just a brief mention of the “average age” in the 260-page report, and the number was derived from only 107 interviews with girls, found either in the street or in the care of human service agencies. So it’s pretty slim research for such a widely cited statistic.

Yet somehow this figure lives on in the echo chamber of Washington discourse. The worst example we found was a Department of Homeland Security pamphlet for school administrators that boldly displayed both the claim about 300,000 children and the average age of 13. It listed two sources: The Department of Justice and the congressionally mandated National Center for Missing and Exploited Children.

But the DOJ reference was to another opinion article that cited the Estes/Weiner report, not an official DOJ finding. And the NCMEC fact sheet referred to a report by Shared Hope International, an anti-trafficking group, which in turn relied on … the same Estes/Weiner report.

So one government agency appears to cite two other government entities — but in the end the source of the data is the same discredited and out-of-date academic paper. It would be amusing if it were not so sad.

The Estes/Weiner report is also uncritically cited in other government documents, such as a Health and Human Services 2009 review of the literature on human trafficking.

By their nature, surveys of sex workers are mainly anecdotal and only provide a snapshot of a particular situation in time. So it’s a mistake to generalize so broadly from any such survey.

If anything, there is some indication that the “13” number may best refer to the average age of a street sex worker’s first sexual encounter. This was reflected in a 1982 survey of 200 current and former juvenile and adult street sex workers in the San Francisco area in which the average age of first intercourse was 13.5 years, as well as in other surveys. But entry in the sex trade is more likely to be between 15 and 16 years old.

A careful 2008 study of 329 sexually exploited youth in New York City for the National Institute for Justice, by researchers at John Jay College, found that the average age of entry into the sex trade was 15.15 years for females and 15.28 years for males. But the researchers warned that the data is fuzzy because there is no way to check the veracity of the accounts offered by the youth. Interestingly, 90 percent of those interviewed reported not having a pimp.

Dominique Roe-Sepowitz, an associate professor at Arizona State University and director of the Office of Sex Trafficking Intervention Research, makes a distinction between those who enter sex work before and after age 18. (The Federal Trafficking Victims Act of 2000 set 18 as a dividing line for the sale of sex, no matter the age of consent in a state.) That makes a difference, because surveys indicate that most sex workers enter the business after the age of 18.

She surveyed nearly 500 adults who were arrested and sent to a court-ordered diversion program. About 30 percent engaged in sex work before age 18, and reported their average age of entry was 14.7 years. The rest, who engaged in sex work after age 18, reported an average age of entry of 25.1 years.

New Zealand has legalized prostitution and regularly issues reports on the sex trade in the country. A 2007 survey found that fewer than 20 percent of those surveyed entered the sex trade before the age of 18.

In fact, a 2011 John Jay study, also funded by the National Institute of Justice, of the sex trade in Atlantic City found very few examples of commercial sexual exploitation of minors. (Here, again, nearly 90 percent of workers reported they had no pimp.)

Klobuchar’s staff expressed surprise at our findings and said the senator should not be singled out because she had relied on what she considered to be government data. “We need to look more closely at the statistics,” said one aide. “There has been no reason until now to question the data that we have used from government agencies.”

“Members of Congress, including Senator Klobuchar, relied on data currently available on the Web sites of the Federal Bureau of Investigation, the Department of Homeland Security, and the Department of Health and Human Services, among others,” said spokeswoman Julia Louise Krahe. “There is a need for better data in this area, that is why the recently passed Cornyn-Klobuchar legislation to combat sex trafficking includes an effort to identify data gaps that can help prevent children from becoming victims of trafficking.”

The Pinocchio Test

All too often, politicians, the media and government agencies have cited thinly sourced and dubious statistics when speaking about human trafficking, apparently because numbers such as “13” have shock value. But advocates hurt their cause when they cite numbers that are easily debunked.

The Fact Checker expects politicians to verify data before using it in public statements, and that certainly means taking an extra step to determine the source of the information. But The Washington Post and other news organizations also failed by allowing Klobuchar’s claim to be published as an actual fact. And Homeland Security should withdraw its inaccurate pamphlet. This is a Four-Pinocchio statistic and should no longer be cited.